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Diffstat (limited to 'src/Language/GraphQL/Lexer.hs')
| -rw-r--r-- | src/Language/GraphQL/Lexer.hs | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/src/Language/GraphQL/Lexer.hs b/src/Language/GraphQL/Lexer.hs index 655be3d..8ca03bf 100644 --- a/src/Language/GraphQL/Lexer.hs +++ b/src/Language/GraphQL/Lexer.hs @@ -1,5 +1,8 @@ {-# LANGUAGE ExplicitForAll #-} {-# LANGUAGE OverloadedStrings #-} + +-- | This module defines a bunch of small parsers used to parse individual +-- lexemes. module Language.GraphQL.Lexer ( Parser , amp @@ -22,6 +25,7 @@ module Language.GraphQL.Lexer , spread , string , symbol + , unicodeBOM ) where import Control.Applicative ( Alternative(..) @@ -44,6 +48,7 @@ import Text.Megaparsec ( Parsec , notFollowedBy , oneOf , option + , optional , satisfy , sepBy , skipSome @@ -73,9 +78,11 @@ spaceConsumer = Lexer.space ignoredCharacters comment empty comment :: Parser () comment = Lexer.skipLineComment "#" +-- | Lexeme definition which ignores whitespaces and commas. lexeme :: forall a. Parser a -> Parser a lexeme = Lexer.lexeme spaceConsumer +-- | Symbol definition which ignores whitespaces and commas. symbol :: T.Text -> Parser T.Text symbol = Lexer.symbol spaceConsumer @@ -213,3 +220,7 @@ escapeSequence = do _ -> return escaped where step accumulator = (accumulator * 16 +) . digitToInt + +-- | Parser for the "Byte Order Mark". +unicodeBOM :: Parser () +unicodeBOM = optional (char '\xfeff') >> pure () |